I got my reasonably priced workers comp policy through GTM, who has been doing my payroll and paying my taxes too.

I carry worker's comp. Some Homeowner's policies will add it on for you. If not, you can buy it from a state exchange (much more expensive that way).

You may also want to get an umbrella policy.

I've heard that liability insurance is required for anyone working in your home. What does this mean? Do people get coverage on top of normal homeowner's policies?